560SEL 1989 won't start

[zcc]

Dear all,
recently I changed the black E.H.A. Valve that is mounted on the fuel distributor (Bosch# 3.437.010.040) with a brand new original one. After that the car run smoothly with no problems at all and no black smoke. I noticed that when the car is a bit cold it won't start. I was too afraid of the EZL unit but thanks god it was fine. The car will run only if I disconnected the black E.H.A. Bosch Valve wires. I did all what I thing it's possible cause including changing the ABS/ASR computer.

What shall I do? Thank you in advanced : ))..

The part is here: http://catalog.eautopartscatalog.com/mercedesshop/sophio/wizard.jsp?partner=mercedesshop&clientid=catalog.mercedesshop&baseurl=http://catalog.peachparts.com/&cookieid=1VE10RDJ21VH18GGU2&year=1989&make=MB&model=560-SEL-001&category=C&part=E.H.A.+Valve

[zcc]

up...

[david s poole]

why did you change the eha?

[Mike Freeman]

Did the wires come out of the plastic connector when you were working on the EHA? Perhaps the wires are reversed thus leaning the mixture when cold.
After the EHA replacement did you reset the mixture? Maybe it's too lean.
Do you have the equipment to check Lambda?
Mike

[zcc]

Mr. david s poole,
I changed it because the old one is causing a black smoke and was too old, in addition, many technicals recommended me to change it.

Mr. Mike Freeman,
No, the wires are still in the plastic connector as its original shape.

I changed the passenger side computer but that didn't solve the problem. It's Euro car.

[david s poole]

there are two diff ones that look exactly the same except for the number on the top.one ends in 007 the other in 003.which one do you have?

[just-n-time]

Have you checked the Ma reading at the EHA? look up some of my entries on the EHA. I have just completed doing one on a 420sel, though Dave will know a hole lot more than I about your car,my notes may be of some help to you.JNT

[zcc]

Thanks to all of you
Problem solved by disconnecting O2 sensor connectors. Now my last question is that what will happen if I did not got a new O2 sensor and left it disconnected for ever?

[zcc]

No!!! The problem hasn't been solved I thought so but it didn't. Please tell me what to do. Could it be the cold starting valve?

[Mike Freeman]

Respectfully; You can't just change parts and expect the fuel management system to be dialed in ! After replacing the EHA you will have to adjust the mixture to achieve proper fuel / air ratio. Mike

[zcc]

Originally Posted by Mike Freeman

Respectfully; You can't just change parts and expect the fuel management system to be dialed in ! After replacing the EHA you will have to adjust the mixture to achieve proper fuel / air ratio. Mike

Of course I did adjust the mixture.

[zcc]

It's driving me crazy, can it be the CIS valve that has 4 pins?